Hypodermic needles



Sept. 15, 1959 T, wm s 2,904,045

HYPODERMIC NEEDLES Filed April 14, 1958 INV EN TOR.

$1 .4. rA ams a/mvas, BY

United States Patent .HYPODERMIC NEEDLES Thomas Owings, Milford, Ill.

Application April 14, 1958, Serial No. 728,259

8 Claims. 01. 123-221 I This invention relates to hypodermic needles andhas, as one purpose thereof, the provision of a hypodermic needle havingcertain specific advantages over those presently known.

Hypodermic needles presently widely employed in the injection of fluidsinto the flesh of human patients and, by veterinarians, into the fleshof animals generally comprise hollow tubes having a beveled forward endserving as a point. In use these needles cause pain as the needlesimultaneously cuts and spreads the flesh; often a plug of tissuebecomes embedded in such needles and they are diflicult, if notimpossible, to reuse and as they are used the initially heavy pressurerequired for insertion becomes noticeably greater. It is accordinglyamong the purposes of my invention to provide a hypodermic needle freeof all such disadvantages.

Another purpose is to provide a hypodermic needle having an end portionof a particular configuration effective to produce a thin slit as theneedle penetrates flesh.

Another purpose is to provide a hypodermic needle having an end portionof a particular configuration effective to greatly reduce, if noteliminate, the likelihood of clogging of the needle as' the shankpenetrates deeper into flesh after the initial penetration of the needlepoint.

Another purpose is to provide a hypodermic needle which may be caused topenetrate the flesh to its operative depth with a minimum of pain to thepatient, a minimum of damage to the tissue and without cutting a plug oftissue.

Another purpose is to provide a hypodermic needle which may be caused topenetrate the material of the stoppers or covers commonly employed uponthe containers for the fluid to be injected without the cutting of aplug of such material and, consequently, without the danger of pluggingthe needle or contaminating the fluid with such plug or pieces ofstopper material.

Another purpose is to provide a hypodermic needle having a pointedportion effective to provide a thin slit in the flesh of the patient,human or animal, the length of said slit being greater than the diameterof the needle body.

Another purpose is to provide a hypodermic needle having a pointedportion effective to provide an initial slit in the flesh of the patientand having an adjacent portion effective to spread said slit, with aminimum of pain to the patient and damage to the tissue, to permit entryof the needle body or shaft into the flesh of the patient.

Another purpose is to provide a hypodermic needle which may be insertedin the flesh of a patient with a minimum of pressure.

Another purpose is to provide a hypodermic needle which may be easilyand effectively sharpened for reuse.

Other purposes will appear from time to time during the course of thespecification and claims.

I illustrate my invention more or less diagrammatically in theaccompanying drawings, wherein:

Figure 1 is a top plan view illustrating the end portion "ice and amajor segment of the body portion of the needle of my invention;

Figure 2 is a side elevation illustrating the device of Figure Figure 3is a bottom view;

Figure 4 is a View taken on the line 4-4 of Figure 2;

Figure 5 is a view taken on the line 55 of Figure 2; and

Figure 6 is a side elevation similar to that of Figure 2 andillustrating a variant form of my invention.

Like parts are indicated by like numerals throughout the specificationand drawings.

Referring now to the drawings and particularly to Figure 1, the numeral1 generally indicates the hollow tubular shaft or body portion of thehypodermic needle of my invention. The needle 1 has its flesh-contactingor outer end portion 2 formed with a flattened slit-forming pointsegment 3 and a rear or flesh-spreading heel portion 4. The portion 3has a sharp point 5 at its outermost end. The portion 3 has rearwardlydivergent, oppositely disposed cutting edges 6, 7 extending from thepoint 5 rearwardly to points adjacent to and outwardly spaced from theheel portion -4 as indicated at 8, 9. The segment 3 includes rearwardlyconvergent, generally curved or rounded edge segments 10, 11 extendingfrom the points 8, 9 to the base of the heel portion 4.

As may be clearly seen in Figures 4 and 5 the edges 6, 7 are sharpenedas indicated at 12, 13 to provide cutting action as the needle 'of myinvention penetrates the flesh of the patient. While the portion 3 is ofextremely thin and flat configuration, it will be realized that thesurfaces 12, 13 are created by grinding to provide the maximum sharpnessof the knife edges or razor-like cutting edges 6, 7.

Similarly, the edge segments 10, 11 are rounded and smooth to insureagainst tissue damage as the needle of my invention is withdrawn fromthe flesh of the patient.

It will be observed that the base of the point portion or segment 3,extending between the points 8 and 9 is of an extension greater than thediameter of the needle shaft 1.

Lying in a plane angularly disposed with relation to the longitudinalaxis of thet shaft or needle body 1 is the heel segment orflesh-spreading portion 4. A beveled arcuate surface 15 is formed alongand defines the rearwardly, upwardly inclined heel portion 4 to providefor maximum ease in spreading the tissue, in which a thin slit is formedby the needle portion 3, as the needle further penetrates the flesh ofthe patient.

Referring now to the variant form of my invention illustrated in Figure6, it will be understood that the portion 3 illustrated therein issubstantially identical with that illustrated in Figures 15. The heelsegment 4a illustrated in Figure 6 compares generally with the portion 4illustrated in 'Figures l-5 with the exception that the beveled surface15 thereof is formed in two planes, each angularly disposed withrelation to the longitudinal axis of the tube or needle shaft 1. Thusthe surface 15 of Figure 6 includes a first portion 15a extending fromthe needle point portion 3 upwardly and rearwardly at a first angle withrespect to the longitudinal axis of the needle 1, and a second segment15b extending from the upper edge of the segment 15a to the rear of theheel portion 4 at a lesser angle with respect to the longitudinal axisof the needle 1. It will be realized, while not illustrated, that thesegment 15b is of generally arcuate configuration while the segment 15ais in two parts, each constituting a continuation of the opposite endsof the segment 15b.

Whereas I have described and claimed a practical and operative device,nevertheless, many changes may be made in the size, shape, number anddisposition of parts without departing from the spirit of my invention.I therefore wish my description and drawings to be taken as, in a broadsense, illustrative or diagrammatic, rather than as limiting me to myprecise showing.

The use and operation of my invention are as follows: The point 5 of theneedle of my invention is brought into contact with the flesh of thepatient. With a ininimum of pressure, due to the sharp point 5, thethin, flat point portion 3 and the razor-like edges 6, 7 extendingrearwardly in gradually diverging paths, the needle of my invention maythen be caused to penetrate the flesh of the patient. I 7

When the needle of my invention has penetrated the flesh of the patientsufliciently to embed the portion 3 to such depth as to embed the points8, 9 of the portion 3, a very thin slit will have been formed in theflesh of the patient. Because the points 8, 9 are spaced apart adistance greater than the diameter of the needle 1 the heel portion 4may then penetrate this slit,- in response to continued inward movementof the needle 1, and the tissue is thereby simply and easily, with aminimum of pressure and a minimum of pain to the'patient, separated bythe angularly disposed surface 15 or surfaces 15a, 15b. Since the tissueis simply spread there is no cutting required on the part of the surface15 and therefore there is virtually no likelihood of further cutting ofthe tissue or forming of a plug of tissue within the needle shank orshaft 1.

Thus the entire circumference of the needle shaft is caused to passeasily into the tissue of the patient, through the slit formed by thepoint 3 with a minimum of binding or friction. Moreover, the consequentreduction in pressure necessary to cause the needle to penetrate thetissue gives to the practitioner more control over the point of theneedle since heavy pressure or tissue friction is not binding the shaftthereof.

I claim:

1. A hypodermic needle comprising a hollow tubular shaft, a pointed endon said shaft, said pointed end comprising a substantially flat segmentof relatively thin cross-section and having rearwardly divergingoppositely disposed cutting edges, said edges terminating at pointsspaced apart a distance greater than the diameter of said shaft.

2. The structure of claim 1 characterized by and ineluding an endsurface on said shaft extending rearwardly from a point adjacent therear edge of said flat segment and lying in a plane angulary disposedwith relation to the longitudinal axis of said shaft.

3. In a hypodermic needle a hollow tubular shaft, a flesh-penetratingportion on said shaft, said portion comprising a substantially flatflesh-cutting point segment lying in a plane generally paralleling thelongitudinal axis of said shaft, and having rearwardly divergingoppositely disposed cutting edges effective to cut a slit having alength greater than the diameter of said shaft and a flesh-spreadingsegment extending rearwardly from said point segment and lying in aplane angularly disposed with respect to the longitudinal axis of saidshaft.

4. In a hypodermic needle a flesh-penetrating and cutting point thereforcomprising a substantially fiat end portion of relatively thin crosssection, said portion hav ing a base wider than the diameter of theneedle with which it is employed, said portion having oppositelydisposed sharpened cutting edges extending forwardly from said base andlying in converging planes, said edges converging forwardly of said baseto form a sharp point.

5. In a hypodermic needle a hollow tubular shaft, an end for said shaftcomprising a substantially flat portion of relatively thincross-section,- said end portion lying in a plane paralleling thelongitudinal axis of said shaft and having a sharpened point at itsouter end and having rearwardly diverging cutting edges extendingrearwardly from said point and terminating at points spaced apart adistance greater than the diameter of said shaft.

6. The structure of claim 5 characterized by and including aflesh-spreading heel surface formed at the outer end of said tubularshaft and extending from the base of said end portion rearwardly in afirst plane angularly disposed with respect to the longitudinal of saidaxis and continuing in a second plane angularly disposed at a lesserangle to said axis.

7. The structure of claim 5 wherein said cutting edges are formed by theconvergence of upper and lower beveled surfaces extending from saidpoint rearwardly to said spaced terminal points.

8. The structure of claim 6 characterized by and including a pair ofrounded shoulder edges lying in rearwardly converging planes andextending from said oppositely spaced terminal points of said cuttingedges to the base of said flesh-spreading surface.

References Cited in the file of this patent UNITED STATES PATENTS145,217 Leiter Dec. 2, 1873 422,436 Otto Mar. 4, 1890 1,601,709 AndersonOct. 5, 1926 2,409,979 Huber Oct. 22, 1946 2,601,580 Yanus June 24, 19522,711,733 Jacoby June 28, 1955 2,717,599 Huber Sept. 13, 1955

